TM 10-4610-232-34
Table 2-1. Direct Support Troubleshooting Guide (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
(a) Repair any loose or damaged wire (para. 2-20),
(b) Replace circuit breaker CB7 if open (para. 2-23).
(c) Replace switch PB3 if open (para. 2-22),
(d) Replace switch SS3 if open (para. 2-22),
(e) Replace PB4 if it does not show continuity when pressed (para. 2-22).
Step 6. Check continuity, point-to-point, from PB4(1A4) to relay K2(K1). Depress the indicating plunger on K2 when
checking across its contact.
(a) Repair any loose or damaged wire (para. 2-20).
(b) Replace K2 if its contact does not show continuity when the plunger is depressed (para. 2-23).
(c) Replace K1 if its contact is open (para. 2-23).
Step 7. Remove the wires from A1X/A1Y on relay K2. Check for continuity across the Al contact when the indicating
plunger on K2 is pushed in.
If there is no continuity, replace K2 (para. 2-23).
Step 8. Check the wires removed in step 7 for continuity and damage to their next connection point.
(a) Repair any loose or damaged wire (para. 2-20).
(b) If all the checks performed in steps 5-8 are satisfactory, replace K2 (para. 2-23).
Step 9. Shut down ROWPU and generator. Refer to electrical drawings in Appendix E and place SS3 in the clean
position. Remove the K1 and K2 wires from K3. Check continuity, point-to-point, from transformer T1(X1) to
relay K3(K2). Repeat the procedure from T1(X2) to relay K3(K2).
(a) Repair any loose or damaged wires (para. 2-20).
(b) Replace circuit breaker CB7 if open (para. 2-23).
(c) Replace switch PB3 if open (para. 2-22).
(d) Replace switch SS3 if open (para. 2-22).
(e) Replace PB4 if it does not show continuity when pressed (para. 2-22).
Step 10. Check continuity, point-to-point, from PB4(2A3) to relay K3(K1). Depress the indicating plunger on K3 when
checking across its contact.
(a) Repair any loose or damaged wires (para. 2-20).
(b) Replace K3 if its contact does not show continuity when the plunger is depressed (para. 2-23).
(c) Replace K1 if its contact is open (para. 2-23).
Step 11. Remove the wires from A1X/A1Y on relay K3. Check for continuity across the Al contact when the indicating
plunger on K3 is pushed in.
If there is no continuity, replace K3 (para. 2-23).
Step 12. Check the wires removed in step 7 for continuity and damage to their next connection point,
(a) Repair any loose or damaged wires (para. 2-20),
(b) If all the checks performed in steps 9-12 are satisfactory, replace K3 (para. 2-23).
3. ROWPU control circuits do not work. (Ref. Schematic diagram FO-1, sheet 5, schematic lines 513-525).
Step 1. Check generator voltage. It must be 435-445 VAC on all three phases,
(a) Adjust to correct voltage.
(b) If voltage cannot be adjusted to correct voltage, refer to generator troubleshooting.
Step 2. Shutdown ROWPU and generator. Refer to electrical drawings in Appendix D and remove the H1, H2, X1 and
X2 wires from transformer T1 (REF: Interconnection diagram FO-2, Sheet 10), Check continuity, point-to-
point, from the power distribution block (PDB) (REF: Interconnection diagram FO-2, Sheet 10) to transformer
T1, wires AL1 to T1(H1) and AL2 to T1(H2).
(a) Repair any loose or damaged wires (para. 2-20),
(b) Replace circuit breaker CB15 (REF: Interconnection diagram FO-2, Sheet 10) if it is open on either
phase (para. 2-25).
Step 3. Check continuity, point-to-point, from T1(X1) to PB3(1B1) and to PB3(2B2) (REF: Interconnection diagram
FO-2, Sheet 11), Repeat the procedure from T1(X2) to terminals 1-80 and 1-73.
(a) Repair any loose or damaged wires (para. 2-20).
(b) Replace circuit breaker CB7 (REF: Interconnection diagram FO-2, Sheet 8) if either side is open (para.
2-23)
Change 1
2-57
